Anti-estrogen compounds are now widely used in the treatment of human breast cancer. One of the most widely used of these compounds is 1-(p-.beta.-dimethylaminoethoxyphenyl)-trans-1,2-diphenylbut-1-ene (tamoxifen). A description of a pharmaceutical composition containing 1-(p-.beta.-dimethylaminoethoxyphenyl)-trans-1-(p-hydroxyphenyl)-2-phenylb ut-1-ene is given in D. N. Richardson's U.S. Pat. No. 4,198,435. The exact mechanism of action of these compounds is not known and while it is well documented that tamoxifen and related triphenylethylene compounds compete for the estrogen receptor (ER), the actual mechanism(s) by which they inhibit tumor cell growth and/or cause cell death has been obscure. More recently, a second high-affinity saturable binding site (anti-estrogen binding site, AEBS), which may interact with the alkylaminoethoxy side chain of triphenylethylene derivatives has been described in a range of normal human tissues and in human breast cancer cells.
N,N-dimethyl-2[(2-phenylmethyl)phenoxy]ethanamine (also known as phenyltoloxamine) and its water soluble hydrochloride are described by L. C. Cheney et al, J. Am. Chem. Soc., 71, 60-63, 1949. A slightly different synthesis of the diethyl form of the same ortho compound is given in H. J. Engelbrescht's West Germany Pat. No. 1,269,134 and his U.K. Pat. No. 961,275. These compounds have pronounced anti-histamine effects.